def hello(a):
    try:
        arr = [1,6,2]
        b = arr[a]
        
        return 0
    except Exception:
        """return 1"""
    finally:
        print("执行结束")
        """return 2 #如果finally右return，则必走return"""
    return -1
if __name__ == '__main__':
    print(hello(5))
    
